Which of the following is NOT an example of a service provider?

A security auditor does not fit the definition of a service provider in the context of the PCI DSS framework. Service providers are typically entities that store, process, or transmit cardholder data on behalf of another entity. This includes payment gateways, Independent Sales Organizations (ISOs), and data center hosting providers, all of which actively engage in managing data and ensuring compliance with security standards for payment processing.

On the other hand, security auditors are third-party professionals or firms that assess and validate the security practices of organizations. Their role is to evaluate compliance and provide assurance about the security measures in place, rather than directly handling or transmitting cardholder data. This distinction is important because the responsibilities and roles of service providers directly relate to the management of sensitive payment information, while auditors are focused on assessment and reporting rather than data handling.